Function Graph with Branch

A logic.function node ("isEven") authored in blueprint mode — a nested visual node graph instead of hand-typed code — using controlFlow.branch to fork execution and a function-scoped Variable to carry the result back out.

Nodes involved (inside the function's nested graph): logic.graphEntry, controlFlow.branch, variable.set, variable.get, logic.graphReturn. On the main canvas: the same logic.function node (private — never wired to an Export, so it stays a file-local helper), called directly by name from a code-mode logic.handlerFunction node attached to the route.

The nested graph: Start → Branch (condition n % 2 === 0, a literal expression, not wired) → True arm sets a result variable to true, False arm sets it to false. A Get Variable node feeds the Return node's value — since reading a variable is always safe regardless of which arm set it, this sidesteps the restriction that a Branch/Switch arm's own values can't be read directly from the Return node (see How Code Generation Works). Open this function's "Blueprint Graph" from its config panel to see the two-arm graph on canvas.

Generated server.js

const express = require("express");

const app = express();

function isEven(n) {
  let result = false;
  if (n % 2 === 0) {
    result = true;
  } else {
    result = false;
  }
  return result;
}

function handler(req, res, next) {
  const n = Number(req.query.n ?? 0);
  res.status(200).json({ n, isEven: isEven(n) });
}

app.use(express.json());

app.get("/is-even", handler);

app.listen(3004, () => {
  console.log("Server running on port 3004");
});

Run it

npx visual-node examples/04-function-graph-branch

curl "http://localhost:3004/is-even?n=4"   # {"n":4,"isEven":true}
curl "http://localhost:3004/is-even?n=7"   # {"n":7,"isEven":false}